Definition of 主 (す)
す
                        主
す
su
suffix
•
                
honorific (or familiar) suffix used after a name(archaism, honorific language)
Other readings:
                子【す】
                Related Kanji
| 主 | lord, chief, master, main thing, principal | 
| 子 | child, sign of the rat, 11PM-1AM, first sign of Chinese zodiac |